Early Friday, several websites owned and operated by the US government were defaced as part of latest protest against online censorship. Anonymous, the elusive hacktivist group known for masterminding similar assaults, is taking credit.

At least half a dozen federal websites belonging to the United States government were disrupted in the latest Anonymous-led assault this week. The US Federal Trade Commission was the primary target of the infiltration, and along with it Anonymous managed to take down the sites for National Consumer Protection Week as well as the Consumer Protection Agency, the Federal Trade Commission and others.

In place of the websites’ traditional homepages, Anonymous operatives left a message to the US government and other international bodies: world leaders should rethink the Anti-Counterfeiting Trade Agreement, or ACTA — an in-the-works agreement between more than a dozen major nations.

Should ACTA pass, a new series of laws could crackdown on Internet freedom by internationally imposing sanctions on ISPs and casual web surfers who are alleged to engage in copyright infringement. In a missive posted on the homepages of the government sites, Anonymous warns that the passage of the bill would bring forth a firestorm of opposition from the hacktivists, who make claims to have already compromised a trove of data from federal employees linked to ACTA, including personal correspondence, passwords and bank account info.

“If ACTA is signed by all participating negotiating countries,” reads the latest message from Anonymous, the world can expect a “war that [will] rain torrential hellfire down on all enemies of free speech, privacy and internet freedom.”

“We will systematically knock all evil corporations and governments off of our internet,” they add.

“There is no doubt that ACTA is more dangerous and detrimental to our rights than SOPA,” they continue, comparing the could-be law to the now hibernating Stop Online Piracy Act that asked for similar legislations only for America. “ACTA will further spread the contagion of stricter copyright enforcement worldwide, at the expense of our essential liberties and basic freedoms of speech, expression and privacy,” continues the message.

“ACTA is a downright shitty act. We must kill it. With fire.”

The Electronic Frontier Foundation (EFF), an Internet advocacy group that has also opposed both ACTA and SOPA, agrees that the latest legislation up for vote is as detrimental to online freedom as Anonymous makes it out to be. On their own site, the EFF says the ACTA raises “significant potential concerns for consumers’ privacy” as well as “the free flow of information on the Internet.”

The US, EU, Switzerland, Japan, Australia, the Republic of Korea, New Zealand,

Mexico, Jordan, Morocco, Singapore, the UAE and Canada are all currently negotiation the verbiage of the ACTA. Attacking the cloak of secrecy that has masked public perception of the bill so far, Anonymous says “It raises substantial questions of governmental transparency as well as democratic accountability, with participating leaders deliberately bypassing their constituents by participating in this shady, backroom process.”

“Because ACTA is an international agreement binding under the general principles of international law, national legislatures would be unable to change domestic copyright law if they eventually feel the ACTA regulations to be too strict. A country would have to literally withdraw from the treaty first, a historical rarity,” explains Anonymous.

This week’s assault comes as the latest installment in a weekly series of Anonymous-led attacks on government websites, dubbed FuckFBIFriday. In past episodes the group has gone after the Department of Justice, the White House and other high-profile government sites. Last week, the group managed to successfully cripple the website of the US Central Intelligence Agency, or CIA.